Investigation and comparison of bare-dihydrogenated junction rectifiers of graphene and silicene nanoribbons

摘要

Although silicon and similar bulk materials are widely used in today's integrated circuits, the transition to lower dimensional structures such as two-dimensional graphene, one-dimensional graphene nanoribbons (GNRs) and silicene nanoribbons (SiNRs) seems inescapable due to the increment of inelastic scattering and related performance degrading effects in bulk circuit components. In this context, GNRs and SiNRs provide advantages such as low area consumption and the adjustment of their electronic behaviours by edge states and widths. On the other hand, rectifiers together with their static and dynamic behaviours constitute the basics of the electronics technology. In this paper, rectifier characteristics of bare-dihydrogenated junctions of GNR and SiNR structures are investigated and compared utilizing first-principles approach. Density functional theory in combination with non-equilibrium Green's function formalism are used to obtain current-voltage characteristics, transmission eigenstates and dynamic electron densities of the considered GNR and SiNR rectifiers and then these quantities are processed to obtain the dynamical resistance, junction capacitance and time constants of these structures, which is essential for graphene and silicene based electronics design. The paper is concluded with the discussion of the large-signal and small-signal performances of the considered GNR and SiNR rectifiers for commercial integrated circuit applications.